1. Field of the Invention
This invention relates in general to a switch, and in particular to a retransmission switch box for use, for example, with portable communications devices.
2. Description of the Related Art
Some conventional portable communication devices are operable to communicate with computers, satellite communication (“SATCOM”) link systems, and other conventional portable communication devices. FIG. 1 illustrates a conventional communication system that includes such conventional portable communication devices 102, 104, and further includes cables 110, 114, a SATCOM link system 106, and data circuit-terminating equipment (“DCE”) 112.
The Harris AN/PRC-117F (“PRC”) multi-band, multi-mission man pack radio is an example of such a conventional portable communication device. Local data applications for the PRC include, for example, the use of personal computer data cards such as ViaSat Inc.'s VDC-400 Personal Data Controller (a type II PC or PCMCIA-style) card and Innovative Concepts, Inc.'s PCIDM card for such roles as Tactical Air Control Parties, Forward Air Controllers, Air Liaison Officers, Fire Support Teams and/or Artillery Forward Observers.
Regarding FIG. 1, if both of the portable communication devices 102 and 104 are PRCs, the conventional communication system is operable as follows. The SATCOM link system 106 is operable to relay data from satellite 108 to PRC 102 via cable 110 and to relay data from PRC 102 to satellite 108. In a RETRANSMISSION mode, PRC 102 is operable to retransmit data, which is received from the SATCOM link system 106 to PRC 104. In a DATA mode, PRC 102 is operable to transmit/receive data to/from a point-to-point serial DCE (e.g., a modem or a facsimile machine) 112 via cable 114. In a VOICE mode, PRC 102 is operable to transmit or receive data to or from PRC 104.
The RETRANSMISSION mode extends the range of one conversation by retransmitting it down range to PRC 104 via PRC 102. For example, this is possible when PRC 104 is within an outlying line of sight (“LOS”) of PRC 102, which in turn is in communication with the SATCOM link system 106. PRC 102 is operable to retransmit at a data frequency or modulation scheme that is different than that of the received data.
Applicants recognized that there is a problem associated with PRC 102, when used in the RETRANSMISSION mode. Specifically, if the operator of PRC 102 additionally requires data from DCE 112, cable 110 must be disconnected from PRC 102, and cable 114 must be connected to PRC 102. More specifically, a data port and retransmission port on PRC 102 share a single physical connector such that the operator must physically remove and replace a cable when switching radio operational scenarios. In practice, standard MC2127 connectors at the end of cables 110, 114, though reliable and sturdy, are frustrating and difficult to connect and disconnect from PRC 102. Considerable time and effort, for example, is expended to remove and/or connect these connectors. Such time and effort can be far better spent by a user on the configuration and operation of device 102 itself. Additionally, data or conversations may be lost.
Another disadvantage of the conventional cable configuration is, according to Applicants, that there is no way to quickly establish a communication channel between PRC 102 and PRC 104, when PRC 102 is being used to transmit (or receive) data from the SATCOM link system 106 and DCE 112. This can be particularly critical when an important conversation may come from PRC 104 to PRC 102. Applicants determined that what is lacking is device or method to quickly establish a communication channel between PRCs 102 and 104, even when PRC 102 is in communication with 108 or 112.